Food aversions may develop in cancer patients undergoing chemotherapy. The time interval surrounding a treatment session during which aversions may develop, the types of foods most suseptible to this phenomenon and the persistence of these aversions, however, remain unknown. In addition, the extent to which conditioned aversions modify a patients nutritional status and prognosis has not been ascertained. The purpose of this investigation is to gain insights on these points. An attempt will also be made to block the formation of aversions to familiar, nutritious foods by introducing a nutritionally inconsequential "scapegoat" food to the patient just prior to treatment. Four groups of 25 cancer patients will be recruited. Groups I and II will be treated with gastric distressing therapeutic agents while groups III and IV (controls) will receive treatments not associated with nausea or vomiting. Groups I and III will be exposed to one of two "scapegoat" foods prior to their first course of chemotherapy. Information on the type and acceptability of foods consumed in the 48 hour period surrounding treatment will be obtained via a food recall and record. One week, one month and six months post-treatment, all subjects will re-rate the foods consumed during this period and sample two beverages, one of which will be the "scapegoat" foods. Preference ratings relative to baseline values and proportions of the beverages consumed will serve as measures of conditioned aversions. The weight loss and treatment outcome of patients who develop aversions will be compared to those not forming such aversions. The types of items involved, time of consumption relative to treatment and persistence of aversions will also be assessed. An improved understanding of the nature of conditioned food aversions and potential for blocking their development should facilitate the development of dietary guidelines for chemotherapy patients and, to the extent that aversions influence nutritional status, improve the prognosis for such patients.